


Fe

by ncee



Category: The Avengers (Marvel Movies), The Avengers (Marvel) - All Media Types
Genre: Alternate Universe - Vampire, Avengers (2012) compliant, Crack, Fluff, M/M, Orgasmic Vampire Bite, Tony lacks self preservation skills, Vampire!Steve
Language: English
Status: Completed
Published: 2014-05-29
Updated: 2014-05-29
Packaged: 2018-01-27 01:31:44
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,356
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1710077
Author URL: https://archiveofourown.org/users/ncee/pseuds/ncee
Summary: <blockquote class="userstuff">
              <p>There was something weird about the Captain, it just took three tries for Tony to pinpoint it.</p>
            </blockquote>





	Fe

**Author's Note:**

> The title is the chemical symbol of Iron (Fe) which is the main component of blood (at least the one responsible for the pigmentation of the RBC, heme.) And, hey, IRON man.
> 
> Based off a prompt circulating somewhere in the Superhusbands tag on Tumblr where the Super Soldier serum was told to be derived from the vampire DNA.

The first time Tony noticed something odd about the Great Captain America was during their first fight at the Helicarrier. Harsh words were exchanged between the two—Tony claiming that everything great about the Captain came out from a single bottle and the Captain saying that Tony was a worthless piece of shit (not the same words but totally the same thought). And when the Captain finally asked Tony the million dollar question, “Take that away and what are you?” Tony’s rehearsed retort of “Genius, Billionaire, Playboy, Philanthropist” undeniably made an impact to the Captain’s demeanour. Tony initially thought he was imagining things but he swore with his miniaturized arc reactor that for a second there, the Captain’s irises actually turned a little bit red. Tony wanted to investigate more but the moment broke when the Helicarrier’s alarms blared signalling a breach in their security.

 

 

Unsurprisingly, the second time Tony noticed something odd about the Great Captain America was during a post Mission-Gone-Wrong. Oddly enough, the mission started pretty great with the Captain giving orders and the rest of the Avengers following them. However, as the mission progressed, all hell seemed to have broken loose.  Natasha and Clint were both injured, the Hulk was nowhere to be found and Tony had a near-death experience involving doombots and lasers. Thank the gods that Thor was in Asgard because if he was there _and_ injured, the Captain would be _pissed_.

Tony, sans the Iron Man suit, was walking hastily in a deserted hallway in the Helicarrier, hurrying towards a safe exit to lick his own wounds when a strong grip grabbed his shoulder and forced him to face the Captain.

“Ow!” Tony reached the shoulder that the Captain had a strong grip on and started to fuss over it without looking up the Captain’s face. Hell, it was going to bruise.

“Jeez, Cap, careful! You’re a super soldier and I’m only a vanilla human so you have to be careful with your strength, okay? It wouldn’t really surprise me if I end up having a bruise in the shape of your hand right here. It’s quite kinky actually, I must—“

“Why didn’t you follow my orders?” the Captain asked, less like a yell and more like a roar.

Tony knew he was guilty, his actions earlier in the field were reckless and stupid but being a Stark, he was too proud to admit that. But seeing the rage behind the Captain’s eyes rendered Tony speechless. A rare occurrence, really. Unsatisfied with his speechlessness, the Captain stalked towards him until there were only mere inches distancing them. His nostrils were flaring and his eyes, Tony swore, were bleeding red.

Eye to eye, the Captain asked again, “Stark, why didn’t you follow my orders?”

Tony, for the life of him, was trying so hard to scour his head for the right words to say in reply to the Captain but his brain gave no feedback. His neurotransmitters were shooting blanks. The haze he was trapped in was broken when a loud _bang_ , courtesy of the Captain’s hand meeting the steel wall, brought him back to reality.  He wanted to say, “Oh, because your orders were stupid!” just to get a rise out of the Captain but found that his treacherous mouth was way ahead of him, spilling out the truth.

“Ah—I—I was, uhm, I mean, there was an issue with JARVIS.”

“An issue with JARVIS?”

“Yes, ah—uhm—yeah. JARVIS. He detected movement inside the building and—“

“And did it ever occur to you that the building was near collapsing?”

“Yes. I knew the numbers, the possibility of me being trapped inside the building was great but I couldn’t just leave those people alone! I had to do something!” Tony was now trying his best to let the Captain understand that he did the right thing.

“The Hulk could have done it.”

“He was too far, Cap. He couldn’t have possibly reached the building in time.”

“That was not your call.”

“Yes, it was.”

“No, it wasn’t!” the Captain exclaimed, followed by his hand meeting the steel wall again. “Even if the building collapsed, the Hulk would have survived it. You, on the other hand, would end up a ball of crushed metal. You could have died, Stark!”

“That’s the thing, Cap! I am not dead!” To emphasize his claim, Tony braved himself to snatch the wrist of the Captain’s right hand and gingerly placed the Captain’s palm against the arc reactor in his chest. Something about the gesture, Tony was guessing it was the soft humming of the reactor, seemed to have calmed the Captain enough to lessen the flaring of his nostrils and the tension in his shoulders. It was really strange for Tony to act this way, submission was never his forte but there was just something in the air (or in the Captain’s gaze) that, sort of, tickled his inhibitions. He decided that he needed to look at this predicament later. However, since the damage was already done, Tony thought, “why not go all the way?” and placed his right palm on top of the hand touching his reactor.

Then, Tony said in the most hushed tone he could have ever imagined, “I am not dead, Cap. I’m right here. Do you feel that? While this thing is still glowing and humming and I’m still breathing, I wouldn’t dare miss a chance of ruffling your feathers. I swear, Scout’s honour.”

After a few seconds, the Captain snickered. “Were you even a Boy Scout?”

“Not my point.” Tony replied.

The Captain’s eyes stared back at him under his lashes. Tony noticed that his irises are seeping back from red to those gorgeous baby blues. “I know”, he said.

“I’m not dead, Cap.”

The Captain, surrendering to Tony’s assurance, nodded and slowly slipped his hand from Tony’s hold.

“Just make sure you stay that way, Stark.”

 

 

 

To everybody concerned (specifically the other members of the Avengers), it came quite as a surprise for them to realize that although the amount of time that Tony and the Captain spent on fighting and taunting each other was unchanged, they actually spent a greater amount of time being with each other. It reached the point where Natasha was quick enough of refer to them as “friends” as evidenced by Clint’s claim of hearing them calling each other by their first names. It took a short while for Bruce to catch up on this development and even a shorter while for all of them to think of this pair as a constant tandem. It went so far as calling them as a maybe-platonic couple: “Stark and Rogers”, “Steve and Tony”, “Tony and Steve”, “Iron Man and Captain America” and even “Cap and Shellhead”.

That is why the third time that Tony noticed something odd about the ~~Great Captain America~~ Steve Rogers came as a surprise for him.

The mission went great—no serious injuries, no near death experiences and yey! The Hulk didn’t even run away far. So, after the debriefing, Tony thought of catching up with Steve and inviting him for a celebratory dinner at a diner that they frequently went to just a few blocks away from the Avengers Tower. He went out looking for Steve and asked a random S. H. I. E. L. D.  agent, “Hey, have you seen the Captain?” which was met with a reply of “He’s in the infirmary, sir.” He couldn’t deny he was worried. Steve looked alright earlier in the mission, his shield didn’t dodge any target, he was in peak condition. But, thinking hard, Tony realized the Captain did look a little pale during the debriefing. At one point, sitting across him in the conference room, Tony even realized that Steve seemed a little bit out breath and his eyes were abnormally hooded. At that time he easily discarded these observations  since he knew that Steve never really gets sick plus Steve would be give him the _disappointed look_ if he ever found Tony not focusing in Coulson’s debriefing. After such recollection, Tony walked briskly towards the general direction of the infirmary.

The infirmary had no patients but there were a few nurses and doctors milling about. He looked at bed after bed until he reached one that has its curtains drawn. He supposed that Steve was there.

“Steve? Steve are you here?”

“Yeah, just a minute—“

But Tony, the impatient part of him, grabbed the curtain and yanked it back before Steve even finished his sentence.

Tony, for the lack of a better word, was shocked.

“Steve, is that blood?”

The sight before him, though, boy oh boy, is certainly a sight to be remembered. He should be grossed out but thought, “Come on, it’s Steve, he’s practically as harmless as two-day old puppy.” Steve was holding a Styrofoam cup in his right hand and his legs were dangling on the edge of the bed. Steve’s eyes were wide open, his irises (now, Tony knows his eyes were not playing tricks on him) were crimson in color, his mouth slightly opened with streaks of red liquid evident in the sides of his lips.

It took a while for Steve to come down from the momentary shock and met Tony’s eyes and said,

“Tony, don’t be stupid, it’s just juice. I got a little dehydrated after the mission.”

For what seemed like minutes, Tony pulled out from his unnoticed reverie and said,

“Okay! So, wanna hang out? Get some burgers and fries? Maybe a milkshake? Same place?”

A smirk planted on the Captain’s lips, “Sure, Tony, I could use a burger.”

Tony, then, had his eyes averted towards the rest of the vicinity while Steve surreptitiously grabbed a napkin on the table beside the bed and wiped his lips. Then he stood up and motioned for Tony to follow. “Let’s go.”

“Okay.” Tony replied.

But before Tony got out of the infirmary, he noticed an empty blood bag on the table beside the bed where Steve has just been. It was _A positive_.

 

 

 

A few weeks after the weird infirmary incident, Tony never delved into the details that he should have attended to (which were very Steve-looking-weird-with-red-eyes related). He just concluded to himself that Steve was weird and he was allowed to be weird from time to time.

Tony ran on weird hours. So, he made Steve his alarm clock: Steve usually went for a run at four in the morning but before he does that, he goes down to Tony’s workshop to cajole him into sleeping in a proper bed. Tony knows that he has a much more effective and efficient alarm clock through JARVIS but he knew Steve actually liked _mother-henning_ him.

So, when JARVIS suddenly said, “Sir, it is exactly four o’clock in the morning”, Tony was astonished to notice that Steve was late for his run.

“JARVIS, where is Steve?”

“Captain Rogers is in his room, sir.”

“Bring up his feed, please, JARVIS.”

“Certainly, sir.”

The feed showed Steve in bed, restless and awake. He was making sounds that indicated he was in pain. This got Tony worried.

“Steve’s vitals, JARVIS?”

“Captain Rogers’ cardiac and respiratory rates are quite elevated, sir, but not in an alarming level.”

But Tony was not satisfied. Clearly, Steve looked to be in pain. To satisfy his unease, he decided to come up to Steve’s room. Just to check, of course. (Not to ogle. Come on, Tony, the man is in pain!). Tony took the elevator to Steve’s floor, walked towards the apartment’s door and knocked.

“Steve? Steve, can I come in?”

Tony can actually hear him grunting which only elevated his worries.

“No, Tony. Leave me alone!”

Tony tried to turn the knob but found that it didn’t budge—it was locked. It was unnatural for Steve to deny Tony access to his room or making Tony feel like his presence his unwelcome. He was always welcome when it comes to Steve, _dammit_.

“You’re in pain, Steve. I know. So, whether you like it or not, I will go in. You can hate me later.”

Then Tony paused. Steve gave no answer.

“JARVIS, authorization: Anthony Edward Stark, Captain Rogers’ floor override code: STAR SPANGLED BANNER.”

“Override successful, sir.” JARVIS replied.

The door unlocked itself. Tony stepped inside and wondered why it was so dark. He once told Tony that the view city lights was quite a comforting view for him which helped him in lulling him to sleep. So, it really was not common for Steve to have all of his windows opaque even when he was sleeping. He found Steve sitting up in bed, his back against the headboard, his knees bent right in front of him with his arms hugging his legs and his head leaning against the bent knees, face hidden from Tony’s sight. He was wearing a simple white tank top and a pair of gray sweat pants. When Tony went a little closer, he found that Steve was trembling. Tony, then, decided to sit at the foot of the bed.

“Steve, did you have a nightmare?”

Steve shook his head, face still hidden, and said, “No.”

Carefully, Tony reached to Steve and touched his left ankle. Steve gasped which prompted Tony to withdraw his hand. When he looked up, he realized that Steve’s face was finally unhidden. Tony reached towards the table beside the head of Steve’s bed and turned the lampshade on to get a better view of Steve’s face.

Steve’s skin was so pale that his shadows were of gray and he had dark circles under his eyes. His nostrils were flaring and it seemed like Steve was going through a great effort just to breathe. The best part of all these observations was the unnatural features that Steve, presently, seemed to have. Pray tell that Tony wasn’t imagining things because Steve’s irises have turned vermillion red and his slightly open mouth has his canines exposed—sharper canines, more like _fangs_.

“Steve, are you alright?”

Steve shook his head again. “No.” His eyes now focused on his bent knees.

Tony, feeling brave again, brought his palm to touch Steve’s right ankle again.

Trying to be soothing, Tony coaxed the blonde to confide in him.

“Tell me what’s wrong, Steve. I want to help.”

With this, Steve looked up to face Tony and replied, “I’m so hungry, Tony.”

“Hungry? Oh, what do you want? Burgers? Steak? I’m sure we have them in the fridge, let me just go down and—“

The blonde shook his head again. “No, no, no Tony. Not that. I’m not hungry for that.”

“Then what are you hungry for?”

Tony waited a few seconds for Steve’s response but when it came, he thought it was a non-sequitur from their serious conversation.

“Tony, have I ever told you that you smell so good?”

 _Unbelievable_. _What was he going to say to that? Seriously? This blonde Adonis is trying to kill me_ , Tony thought.

“Uhm—Ah—Thanks?”

Steve slowly released his hold of his legs, his arms and legs momentarily relaxed. Tony noticed Steve’s pupils were so dilated that they nearly took up the whole space of his irises. He, then, had his hands planted on the bed to support his upper torso and leaned close to Tony until his nose was near to a skin-to-skin contact with Tony’s neck. (Tony was not nervous, no he was not.) Steve then sniffed him right there, _like a dog_. He moved his head so that his lips are near Tony’s ear and whispered,

“You smell so good. Good enough to eat, Tony.”

(Tony was nervous now. He was undeniably nervous.)

“Uhm, Cap, is this some kinky thing that you have? Biting? Are you a cannibal? God, I hope not. Do you want to fu—“

Suddenly, the Captain leaned back and said, “No, nothing like that.” As if just realizing how close he was to Tony, he went backwards and leaned his head back against the headboard.

Tony, the ever curious scientist part of him, knew that he was about to tread dangerous waters but that just wasn’t enough to stop him when he said, “Tell me what’s going on here, Steve.”

Feeling helpless, Steve sighed and massaged his right temple with the fingers of his right hand like he was getting a headache out of this conversation. He then looked up to Tony, resolute now on explaining to his best friend his situation.

“Before I was injected with the super soldier serum, Dr. Erskine told me that there were downsides to this. The serum was experimental and there was a possibility that it would remain unstable. But, determined as I was, I pushed through it. You see, the main downside of the serum, which made it unstable in the first place, is the fact that the serum is derived from the vampire’s DNA.”

The expression on Tony’s face was verging on shock. The words that he heard right out from Steve’s mouth were quite unbelievable for him. For him, it was like learning that magic was real. _He hated magic._

“What—so what you’re saying is that you’re a vampire?”

“Part-vampire, Tony. Only a percentage, really.”

Tony was looking quite confused now. “But I read the full report, there was nothing written about vampire DNA being infused in the serum. Did my father know?”

Steve nodded. “Yes, he did. There were only a few people who knew about this—Me, Dr. Erskine, your father, Peggy and Colonel Phillips. This fact was written out of the books. Dr. Erskine told me he was looking for a way to lessen the symptoms that the vampire DNA had but then he was killed. So, I had to live like this.”

There was a light of slight comprehension in Tony’s eyes, it was obvious he had a lot of questions and Steve was prepared to answer him amidst his hunger.

“Are you joking? You’re not joking, right?” Tony asked.

To answer him, Steve bared his fangs and pointed at them with his index finger. “Do these look like they’re joking?”

The brunette smiled. Steve seriously had a weird sense of humor in the middle of a tension-high situation.

“Fair enough. So, question, who else knows about this?”

“Fury, a few medical staff in the infirmary. And now, well, you.”

“I can’t help but ask, though, I know this is quite stupid but still we have battled some outer space aliens and we have greatly established the existence of Asgardian gods, vampires are real?”

Steve, shaking his head, said, “I don’t know, I have never met one before. Dr. Erskine never told me where he got the DNA. But I suppose they are real since, hey, look at me.” He ended that statement with his arms spread.

He never noticed but Tony was inching towards him, being comfortable sitting beside the blonde, part-vampire in bed.  “You know, this explains so much.”

“Such as?”

“Well, I could have sworn the first time we fought in the helicarrier, your irises turned red.”

The blonde’s eyebrows rose towards his hairline, “Really?”

The brunette nodded, “Yes. I could have sworn you glamoured me too and now I’m convinced that you drank blood the last time we were in the infirmary.”

With a grunt, Steve replied “Yes, I did. The thing with the glamouring though, I can’t control it. I mean, I still don’t know how to control it. It just happens and I never meant to do it to you.”

Tony snickered. “It’s okay, though. No harm done. But to bring you back to speed at present, you’re hungry _right now_.”

With that, Steve nodded. Tony could not help but notice the blonde turned a little bit feral-looking after what he said about his hunger.

“When was the last time you fed?”

Now, Steve seemed quite out of breath with him gasping air from his mouth.

“Weeks ago, when you caught me in the infirmary.”

So many thoughts were running through Tony’s head but he knew that Steve was his best friend. _He was also quite attracted to him_ , if he was to be completely honest. He would do anything for him. Being the reckless and selfless person that he is, he made his final decision of saving Steve from his suffering. He inched closer towards the blond, leaned his to the other side as if clearly presenting Steve with his meal.

Steve looked a little bit panicked with his best friend’s action. “Tony, what are you doing?”

“Giving you your meal, stupid. Come on, I know you’re hungry and you told me I smelled nice.”

 _Uneasiness looked like constipation in the Captain’s face_ , Tony dare thought.

“I can’t, Tony.”

“Why the hell not, Cap?”

“I’ve only done this once. I only once bit a human and the rest were just blood out of bags or blood in cups. I might hurt you badly.”

Tony considered this but he was firm in his decision of satiating his best friend’s thirst.

“You won’t hurt me, I promise. I have my suit on-call if you ever hurt me. So, come on, chop-chop _mon capitan_ , bite me already.” Just to emphasize further, he presented his neck more.

“Okay. Alright. Okay, Tony. Just tell me if it hurts too much, okay?”

Hesitantly, Steve placed on hand on the opposite side of Tony’s neck and the other cradling the base of his skull. When Steve lowered his head, he gave Tony’s neck a little kiss (which made Tony giggle a little), then a little lick (which made Tony moan) and then without much ceremony, he brought his fangs down to touch his skin and he bit him.

Tony gasped loudly. The bite hurt, it really did, but then suddenly it felt different. Warmth was felt all throughout his body, his limbs felt like jelly yet in the back of his mind he was still aware that his arms strongly held on to Steve’s shoulders. His mind felt like he just injected himself with a hallucinogen. His vision was hazy and blurry. He was murmuring words that were near unintelligible and he was moaning in between these uttered words. _Oh god. What the hell. Feels so good. Ugh._ The best of all, _the cream of the crop_ , was that he felt a funny feeling down in his crotch. _Oh my god, am I having an erection?_ Tony ought to be self-conscious about this but this orgasm-like thing he was feeling was just too good to ignore.

The sensation lasted for quite a long time, Tony wasn’t sure how long exactly. The next thing he knew he was slowly being brought down to bed by careful hands on both his nape and the back side of his head. The sharp fangs that were stinging him in his neck were withdrawn and a moist tongue was lapping where the fangs used to be. Slowly, his vision cleared and saw two bright blue eyes staring down at him. The owner of the pair of bright blue eyes looked worried. Tony smiled, _oh yeah, it’s Steve_.

“Tony, are you okay?”

Still feeling hazy, Tony gave his best indication of a nod and a smile.

“Never better, Cap. Wow, that was amazing.” _Amazing, too, the feeling of Steve’s fingers carding through his hair._ He badly wanted to say something about the blonde’s other hand cradling his cheek, maybe a joke or two, but felt too hazy to do so. “That was amazing. It felt like I was so high. I’ve never felt that way before. Damn. DAY-UM.”

The gorgeous blonde smiled. “Yeah. I’m glad you liked it. You were moaning a lot.”

“Was I, really?”

“Yes.”

“Good. I see that your eyes are back to normal. Are you full?”

“Yeah. Thank you, Tony.” Steve almost looked shy when he said that.

“You’re welcome, Spangles. Next time you’re hungry come to me, okay?”

Tony, although mind too drunk at the moment, swore to never forget the look on the Captain’s face—eyes comically wide, his mouth (sans fangs) gaping in disbelief. It looked really hilarious. He looked like he just choked on a dick.

“Are you sure?”

“Definitely sure.”

Steve nodded. “Okay.”

Satisfied that Tony was alright, Steve cautiously moved so that he was lying beside the brunette with his cheek supported by his arm so that he could lean over his bed partner. He, then, addressed the building’s AI in a hushed tone, “JARVIS, clear half of the windows.”

JARVIS replied, “Certainly, Captain Rogers.”

They were both quietly lying in bed for a few minutes when Tony noticed the sun slowly rising. He, then, faced Steve with a query, “Does the sun bother you?”

“No, not at all.”

This answer brought a frown to Tony’s face. “Then why do you jog at the most ungodly hour of four in the morning? I thought it was part of your vampiric weirdness.”

The blonde looked amused. “No. I just like waking up early.”

With a scowl that had less effort in it being nasty, Tony said “You’re weird. Who would’ve thought Captain America was a vampire.”

“Part-Vampire, Tony.”

“And _A positive_ , really, Steve?”

“I knew you would bring that up. I was always partial to _A positive_. I don’t know why but it tastes better to me. That’s why you smell so good. And you taste equally good as well.”

“Well, that’s reassuring.”

Tony smiled. He felt sleepy now, what with the blood loss and the shock of a lifetime _hello, Captain America feeds on blood what the hell_. But just before he succumbed to his slumber, he felt something uncomfortably moist down his pants. Curious, he brought his palm towards his crotch, uncaring of Steve’s eyes trailing his motions. Confirming his suspicions through the touch of his palm, his previously drowsy eyelids were now brought back to attention and his eyes turned towards the culprit of his latest embarrassment.

“Cap, you made me cream my pants.”

Steve’s enthusiastic and boisterous laughter following that was more than enough for the momentary shame of Tony Stark being reduced to coming in his pants like a teenage boy.

**Author's Note:**

> kudos and comments, pretty please? :3


End file.
